Compositions and methods for diagnosing alzheimer's disease

Abstract

The present invention provides methods and compositions for the diagnosis of Alzheimer's disease. In particular, the present invention provides modified beta-amyloid peptides, antibodies that specifically bind to the modified beta-amyloid peptides, and methods for using these compositions in the diagnosis of Alzheimer's disease, as well as methods to monitor treatment and/or disease progression of Alzheimer's disease in patients. The present invention also provides compositions and methods useful in research involving amyloid precursor protein (APP) metabolism and Alzheimer's disease.

What is claimed is:  
     
       1. A method for detecting at least one modified β-amyloid peptide comprising at least one malondialdehyde adduct, comprising the steps of: 
       a) providing:  
       i) a sample suspected of containing at least one modified β-amyloid peptide comprising at least one malondialdehyde adduct, and  
       ii) a purified antibody directed against a modified β-amyloid peptide comprising at least one malondialdehyde adduct;  
       b) contacting said sample with said antibody under conditions such that said antibody binds to said modified β-amyloid peptide comprising at least one malondialdehyde adduct, to form an antigen-antibody complex; and  
       c) detecting the presence of said antigen-antibody complex.  
     
     
       2. The method of  claim 1 , wherein said sample is selected from the group consisting of blood, plasma, serum, serous fluid, and cerebrospinal fluid. 
     
     
       3. The method of  claim 1 , wherein said sample is from a subject. 
     
     
       4. The method of  claim 3 , wherein said subject is a human. 
     
     
       5. The method of  claim 3 , wherein said subject is selected from the group consisting of subjects displaying pathology resulting from Alzheimer's disease, subjects suspected of displaying pathology resulting from Alzheimer's disease, and subjects at risk of displaying pathology resulting from Alzheimer's disease. 
     
     
       6. The method of  claim 1 , wherein said method comprises an enzyme-linked immunosorbent assay. 
     
     
       7. The method of  claim 6 , wherein said enzyme-linked immunosorbent assay is selected from the group consisting of direct enzyme-linked immunosorbent assays, indirect enzyme-linked immunosorbent assays, direct sandwich enzyme-linked immunosorbent assays, indirect sandwich enzyme-linked immunosorbent assays, and competitive enzyme-linked immunosorbent assays. 
     
     
       8. The method of  claim 1 , wherein said antibody further comprises a conjugated enzyme, wherein said conjugated enzyme is selected from the group of enzymes consisting of horseradish peroxidases, alkaline phosphatases, ureases, glucoamylases, and β-galactosidases. 
     
     
       9. The method of  claim 6 , further comprising the step of quantitating said at least one modified β-amyloid peptide comprising at least one malondialdehyde adduct in said sample. 
     
     
       10. The method of  claim 6 , wherein said enzyme-linked immunosorbent assay further comprises an alkaline phosphatase amplification system. 
     
     
       11. The method of  claim 6 , further providing at least one capture antibody. 
     
     
       12. The method of  claim 6 , further providing at least one detection antibody wherein said detection antibody is directed against said antibody directed against said modified β-amyloid peptide comprising at least one malondialdehyde adduct. 
     
     
       13. The method of  claim 12 , wherein said detection antibody further comprises a conjugated enzyme selected from the group consisting of horseradish peroxidase, alkaline phosphatase, urease, glucoamylase and β-galactosidase.